The display device market has experienced a rapid change in product trends, away from cathode ray tube (CRT) display devices towards flat panel displays (FPDs). Representative examples of FPDs are Liquid Crystal Displays (LCDs), Plasma Display Panels (PDPs), Organic Light Emitting Diode (OLED) display devices, and the like, all of which are lighter, thinner, and easier to manufacture in larger sizes, as compared to CRT display devices.
Recently, research into FPDs has achieved technical developments in terms of imparting flexibility to FPDs to allow such displays to be flexible like paper, in addition to having light and thin profiles. It is therefore essential to select a substrate which forms a substantial portion of the thickness of the FPD while serving as a base for the deposition of various elements or protecting elements from the external environment. However, only a limited number of materials satisfy all of these three characteristics, such as being lightweight while having a thin profile and flexibility, while having their own particular advantages and disadvantages. Therefore, it is difficult to actually apply such materials to display substrates.